1. Field of the Invention
The invention relates to an eye imaging system.
2. Description of the Related Art
A typical optical instrument for eye detection or imaging includes a lighting optical path and an observation optical path. The lighting optical path is used to illuminate the eye of the observed, and a reflected light ray from the eye passes through the observation optical path to illuminate on the eye of the observer or an observation device, so that the healthy condition of the eye including fundus is observed and photographed.
However, the eye structure is complicated and the specific physiological tissues vary from one patient to another. Particularly, when using an optical instrument to observe and photograph, surplus reflected light of the cornea and the surface of the objective lens passes through the optical instrument and forms a ghost image. Therefore, the quality of the overall image of observation is lowered, and it becomes necessary to eliminate the ghost image and various stray lights in the optical system.
Conventional ophthalmic optical instruments often employ a black pot plate or an annular aperture to eliminate the ghost image and the stray lights. Specifically, these instruments have the following disadvantages:                1. The ghost image and the stray lights cannot be completely eliminated, and the obtained image quality is poor.        2. The lighting optical path and the observation optical path are independent from each other, and the production cost is relatively high.        3. Optical structures designed for eliminating the ghost image and the stray lights has a relatively complicate structure and occupies large volume.        4. When annular aperture is employed, the availability of the light source is relatively low while the energy consumption is relatively large.        5. The light flux entering the eye of the patient is relatively high, which results in patient discomfort.        
Thus, an eye imaging system that has a high imaging quality, relatively simple structure, low production cost, and energy consumption, good effect on elimination of ghost image, and little by-effect on the eye of the patient is desired.